Wars were not one sided, battles not well coordinated and nations more divided than they were united. The Battle of Trafalgar is one of the few cases where the myth really does live up to the actual history of the battle, and how it dictated British international diplomacy of the next half century.
The battle itself was the culmination of a 6 month long chase. During the Napoleonic Wars the Royal Navy had adopted a strategy of blockading French and Spanish ports to prevent the numerically superior enemy from uniting and attacking British colonies in the West Indies. Britain was also financing the war effort of its allies, so the profitable trade from the West Indies was crucial. Unlike other admirals Nelson adopted a loose blockade at Toulon, allowing the French fleet under Villeneuve to escape in early 1805. Villeneuve initially sailed to the West Indies to disrupt the Atlantic trade, but returned to Europe to join with the Spanish fleet outside of Cadiz. Nelson was dispatched from England as soon as his flagship, HMS Victory, was ready to sail on September 15. The British fleet assembled outside of Cadiz, and following Napoleon’s orders, Villeneuve’s Franco-Spanish fleet left Cadiz to meet battle.
The battle was a masterclass of naval command by Nelson. The British fleet was separated into two lines that attacked perpendicular to the Franco-Spanish line. While this allowed the Franco-Spanish ships to fire before the British ships could return fire, once the British ships dissected the line they would have fire superiority. The higher quality of British gunnery crews and use of the carronade, a short range cannon with devastating capabilities gave them a significant advantage. The battle was an overwhelming victory for the British, who suffered no ship losses; whereas the Franco-Spanish fleet lost 22 ships captured or destroyed.
The battle confirmed British naval supremacy for decades onwards. Continued French victories on land would mean the Napoleonic wars continued for a further decade, but Britain and her colonies were no longer under threat from invasion. Britain continued to finance its allies, allowing them to fight back after successive defeats.